An optically active 2-alkyl-1,1,3-trialkoxycarbonylpropane is a compound useful as a material for formation of an asymmetric carbon atom in synthesis of natural products, pharmaceuticals and so on.
Heretofore, as a method for producing such an optically active 2-alkyl-1,1,3-trialkoxycarbonylpropane, for example, a method of addition of a silyl enolate to an alkylidenemalonate in the presence of an asymmetric copper catalyst (Non-patent document 1) is known. By ester-exchange of the thioester obtained in this production method, an optically active 2-alkyl-1,1,3-trialkoxycarbonylpropane can be obtained. In this method, however, a halogenated solvent is used, and a low temperature condition is required for improving the optical purity of the objective substance. Additionally, even when the reaction is conducted at −78° C., the optical purity is at most 93% ee (43% ee when the alkyl group that binds to the carbon atom serving as optically-active center is a methyl group), so that this method is not necessarily satisfactory from the industrial view.
[Non-patent document 1] J. Am. Chem. Soc., 122, 9134 (2000)